Stud-driving tool



Feb. 24, 19 10 R. TEMPLE Em STUD-DRIVING TOOL Filed June 29. 1967 w RN MN N1 .muumwi mw wm INVENTORS'. ROBERT TEMPLE BY fANEST .5. TEMPLE ATTOR/VEVS.

United States Patent Office 3,497,124 STUD-DRIVING TOOL Robert Temple, Swissvale, and Ernest E. Temple, Murrysville, Pa., assignors to Mine Safety Appliances Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed June 29, 1967, Ser. No. 649,957 Int. Cl. B25c 1/12, N14

US. Cl. 227- 13 Claims ABSTRACT OF THE DISCLOSURE Explosively actuated stud-driving tools that are attached temporarily to the objects that are to receive studs are not new, but when such tools are fired, the recoil separates the barrels from their supports. This not only is dangerous, but when it happens under water the barrels may be lost.

It is among the objects of this invention to provide a stud-driving tool which is fastened rigidly in place during driving, which provides for recoil Without losing the barrel, and which is simple in construction and operation.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. 1 is a longitudinal section through the tool attached to a padeye;

FIG. 2 is a cross section of the tool taken on the line II-II of FIG. 1; and

FIG. 3 is a view similar to FIG. 1, but showing the tool immediately after firing.

Referring to the drawings, an object, such as a padeye 1 through which a stud is to be driven for fastening it to the side 2 of a sunken vessel that is to be raised, has an opening 3 encircled by an externally threaded cylindrical flange 4. This flange may be integral with the rest of the padeye or be a projecting portion of a ring welded in the padeye opening. The flange is designed to support and anchor one end of an extremely high-powered explosively actuated tool while the tool is being fired to drive a stud through the padeye opening and into the vessel. Before the stud is driven the padeye can be held in place by magnets if desired.

The tool includes a metal sleeve 6 having an internal screw thread at its front end that can be screwed onto flange 4. The rear end of the sleeve is provided with an internal annular shoulder 7 that may be formed from the flange ring 8 screwed into the sleeve. The barrel 9 of the tool is slidably mounted in this ring and extends rearwardly a short distance from it. The front end of the barrel is encircled by a shoulder 10 that may be formed by the rear end of a collar 11 screwed onto the barrel, with a sealing ring 12 between them. The barrel supports a bushing 13 that will fit in the padeye opening. The bushing is fastened to the collar in a manner that is sufficient to keep the two connected together only until the tool is fired. Thus, the collar may be provided wih an internal annular shoulder 14, through which a thin tubular projection 15 on the bushing extends, with the rear end of the projection flared out slightly to hold the bushing in place. A sealing 3,497,124 Patented Feb. 24, 1970 ring 16 encircles the bushing and engages the inside of the collar. The front end of the collar may extend into the padeye flange 4 and be encircled by a sealing ring 17 that engages that flange. This sealing ring also serves the purpose of frictionally connecting the barrel with the padeye flange until sleeve 6 can be screwed onto the flange. The bushing 13 has a surface, such as a shoulder 18, that will engage an opposing surface or shoulder in the padeye opening. The front end of the bushing is closed by an integral end wall 19. To prevent water from being trapped in front of shoulder 18 while the bushing is being inserted in the padeye, the bushing is provided with a longitudinal groove 20 that connects the shoulder with the front end of the bushing.

Slidably mounted in barrel 9 is a cup-like piston 21, the rear end of which normally is seated in a recess in the front of a stationary cap 22 encircled by a sealing ring 23. The cap is provided with an axial bore, in which the rear end of a rod 24 is screwed. The rear end of the passage is closed and sealed by a thin wall integral with the cap, as the bore does not extend entirely through the cap. The rod is also screwed into the front end of the piston, from which it extends forward through a spacer 25 slidably mounted on the rod. The rod bolts the piston tightly to the cap. A very short length of the front end of the rod is screwed into the enlarged rear end of a stud 26 that has a pointed front end. By changing the length of the rod and spacer, the velocity at which the stud strikes wall 2 can be varied. A primer cap 27 is mounted in a recess in a rear end of the rod and is connected by an axial passage 28 to radial passages 29 that open into the piston around the rod. The passages and piston are filled with an explosive pow-. der 30. Although the inside of the barrel is supposed to be sealed against the entrance of water, nevertheless it is desirable to apply a sealant to the threads of rod 24 when they extend through the front end of the piston. Behind the piston cap 22 a breechblock 32 is screwed into the rear end of the barrel and supports a rearwardly extending tube 33, in which a firing pin 34 is slidably mounted. A portion of the pin is encircled by a coil spring 35 that urges the spring forward, but the pin normally is held in its retracted cocked position by a U- shape spacer 36 straddling the pin between the rear end of the tube and a knob 37 on the rear end of the pin. The tool also may be fired electrically, if desired, in a well known manner.

When spacer 36 is removed from the firing pin after the sleeve has been attached to flange 4, the spring will drive the pointed front end of the firing pin through a passage 38 in the breechblock and against the back cap 22, which will be bent forward far enough to fire the primer. This will ignite the powder, which will explode and build up sufficient pressure in piston 21 to break rod 24 in a reduced diameter area, whereupon the piston will be driven forward in the barrel behind spacer 25 and the s ud. The spacer and stud will move forward together until the stud has penetrated the solid front end of the bushing and the adjoining wall of the vessel and the head of the stud has come to rest in the bushing as shown in FIG. 3. This will securely fasten bushing 13 to the vessel wall 2 and clamp the padeye between bushing shoulder 18 and the vessel. The padeye is provided with several openings 3 and flanges 4, and driving tools can be connected to all of the flanges and fired at the same time. As the stud is driven forward, piston 21 will be stopped by collar shoulder 14. The recoil produced by the explosion will drive the barrel backward in sleeve 6, causing collar shoulder 14 to straighten flexible bushing projection 15 and pull away from it. Due to the short threaded connection between the front end of the rod and the stud, the few threads will be stripped and the stud and rod will separate. Openings 39 in the side of the sleeve will permit Water to escape as collar 11 moves backward in it.

It is a feature of this invention that a shock absorber 41 is mounted between the shoulder 7 in the rear end of the sleeve and the shoulder 10 around the front end of the barrel. This shock absorber encircles the barrel. When the tool is fired, the shock absorber is crushed by the recoiling barrel and therefore absorbs the shock of the recoil and prevents the shoulders 7 and 10 from striking each other. Preferably, the shock absorber is a coil of metal tubing, in which the convolutions engage or nearly engage one another. Copper tubing is preferred. When the barrel recoils, the convolutions of the tubing will crush and absorb the energy of the recoil. The resistance of the shock absorber to crushing can be varied by changing the size of the tubing, its wall thickness or the metal from which it is made. When the convolutions of the uncrushed coil are close together, the coil is shorter than the distance between shoulders 7 and 10 in order to allow the barrel to move backward in the sleeve a short distance before being restrained by the shock absorber. This gives the stud a chance to become firmly fixed in wall 2 before the rearwardly moving barrel attempts to pull the sleeve and the padeye away from the wall. In case the convolutions of the shock absorber coil are spaced apart an appreciable distance, the ends of the coil could engage both of the adjoining shoulders because the coil would not start to crush and exert an outward force on sleeve 6 until after the convolutions have been moved together, and by that time the stud would be securely embedded in wall 2.

After the tool has been fired, the sleeve can be unscrewed from the padeye flange and the barrel can be pulled out of the front end of the sleeve to permit the crushed shock absorbing coil to be removed and replaced by a new one so that the tool can be reused. The coil is inexpensive and easy to make and install.

We claim:

1. A tool for driving a stud through an object provided with a cylindrical threaded flange, the tool comprising a sleeve provided at its front end with a screw thread adapted to be screwed onto the flange to hold the sleeve, the rear end of the sleeve being provided with an internal annular shoulder, a barrel in the sleeve slidably mounted in said shoulder and encircled at its front end by a shoulder, crushable shock absorbing means disposed in said sleeve around the barrel between said shoulders, means for holding a stud in the rear portion of the barrel, and means connected with the rear end of the barrel for firing an explosive charge to drive the stud forward and out of the barrel, whereby the recoil from said explosion will force the barrel backward in the sleeve against the resistance of the shock absorber.

2. A tool according to claim 1, in which said shock absorber is a coil of metal tubing that is crushed by said recoil.

3. A tool according to claim 2, in which the convolutions of said coil are substantially in engagement with one another, and the normal distance between said shoulders is greater than the length of said shock absorbing means to space at least one of the shoulders therefrom.

4. A tool according to claim 1, including a bushing adapted to fit in said flange and to tightly receive said stud, and means releasably connecting the bushing with the barrel so that the recoiling barrel will pull away from the bushing.

5. A tool according to claim 4, in which the outer end of said bushing is sealed by an integral end wall adapted to be penetrated by said stud.

6. A tool according to claim 4, in which said bushing is provided with a surrounding forwardly facing shoulder for engaging said flange.

7. A tool according to claim 4, in which said bushingbarrel connecting means include a collar rigidly mounted on the front end of the barrel and forming said barrel shoulder.

8. A tool according to claim 4, in which said bushingbarrel connecting means include a collar rigidly mounted on the front end of the barrel and provided with an internal rearwardly facing shoulder, said bushing being provided at its rear end with a flexible portion extending into the collar past the collar shoulder and bent outwardly behind the shoulder.

9. A tool according to claim 4, in which said bushingbarrel connecting means include a collar rigidly mounted on the front end of the barrel and provided with an internal rearwardly facing shoulder, said tool including a stud-driving piston adapted to be driven forward until stopped by said internal collar shoulder.

10. A tool according to claim 1, including a cap rigidly mounted in the rear end of the barrel and provided with an axial bore, a rod rigidly mounted in said bore and extending forward therefrom to support the stud, and a cup-like piston having an open rear end closed by said cap, the piston having an opening in its front end through which said rod extends, the piston being rigidly mounted on the rod and said explosive charge being disposed in the piston around the rod, and said rod being provided with an area inside the piston adapted to break when said charge is fired, whereby to permit the piston to be driven forward in the barrel.

11. A tool according to claim 10, in which said rod is provided with a primer in its rear end and a passage connecting the primer with said explosive charge, explosive powder filling said passage and said firing means include a firing pin for detonating the primer.

12. The combination with a padeye provided with an opening encircled by an outwardly projecting threaded flange, of a tool comprising a sleeve having its front end screwed onto said flange, the rear end of the sleeve being provided with an internal annular shoulder, a barrel in the sleeve slidably mounted in said shoulder and encircled at its front end by a shoulder, a crushable metal coil encircling the barrel between said shoulders, a bushing fitting in said padeye opening and releasably supported by the barrel, the front end of the bushing being closed by an integral end wall, means in the barrel for holding a stud, and means connected with the rear end of the barrel for firing an explosive charge to drive the stud forward and part way through said bushing end wall to fasten the padeye to a support.

13. A tool according to claim 10, including a spacer slidably mounted on said rod in front of the piston.

References Cited UNITED STATES PATENTS 1,365,870 1/ 1921 Temple 227-9 2,189,439 2/ 1940 Temple 2279 XR 2,673,980 4/ 1954 Ballachey et al. 227-9 2,771,607 11/ 6 Skumawitz 2279 GRANVILLE CUSTER, 111., Primary Examiner 

